NEW YORK (Reuters Health) – Even very young children can develop medullary thyroid carcinoma when they bear the RET proto-oncogene mutation, which causes multiple endocrine neoplasia type 2 (MEN 2). Researchers in Argentina recommend prophylactic thyroidectomy as soon as RET mutations are confirmed.
Dr. Marta Barontini, of the Hospital de Ninos R. Gutierrez in Buenos Aires, and associates evaluated members of 16 families with MEN 2A. This form of the disorder causes pheochromocytoma in about half of patients and hyperparathyroidism in about one of five patients.
As reported in the January 15th issue of Cancer, among 98 relatives of the index patients, 26 children and 16 adults were positive for the mutation. Nearly 90% of the juvenile carriers exhibited no clinical or biochemical evidence of thyroid disease.
Eighteen RET+ children, ages 17 months to 21 years, underwent total thyroidectomy. Histopathology of the surgical specimens showed parafollicular cell hyperplasia in all 18 and medullary thyroid carcinoma in 15. Intrathyroid spread was observed in three, while regional lymph node metastasis had already occurred in one.
In addition to prophylactic surgery, Dr. Barontini's group suggests screening for pheochromocytoma, which can be fatal if undiagnosed. Its presence, whether symptomatic or not, highly increases the risk associated with thyroidectomy.